What you can expect

During proton therapy

You typically undergo proton therapy five days a week for several weeks. However, in some cases, you may undergo only one or only a few treatments, depending on your condition. The actual proton therapy treatment may take only a minute or so, but expect to spend about 20 minutes preparing before each treatment session.

To prepare, you'll be positioned on a table or in a chair. Cushions and restraints will be used to hold your body still. Then you'll undergo an imaging test, such as an X-ray or CT scan, to make sure your body is in the same precise position before each treatment.

Your radiation therapy team will then leave the room and go to an area where they can monitor you. They can still see and hear you.

What you experience next depends on the type of proton therapy machine your treatment team uses:

A proton therapy machine that rotates around you. If you're undergoing proton therapy with a machine called a gantry, you'll be placed on a table that is slowly slid into the circular opening of the machine. The machine rotates around you to direct proton beams at precise points on your body.

A proton therapy machine that doesn't move. If you're undergoing proton therapy with a fixed-beam machine, the chair or table you're positioned on will move and the proton therapy machine will remain still. The movement of your chair or table during treatment is controlled remotely by your radiation therapy team. How often your chair or table moves during treatment depends on your situation.

You won't be able to feel the radiation during your proton therapy treatment.

After proton therapy

Once your treatment session is complete, you can go about your day. You won't be radioactive or give off radiation.

Side effects of radiation usually develop over time. You may experience few side effects at first. But after several treatments you may experience fatigue, which can make it feel like your usual activities take more energy or that you have little energy for everyday tasks. You may also notice a sunburn-like skin redness in the area where the proton beams are directed.

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